At an estimated $44k for just the components, that would be a bit outside of "consumer prices". :-)
It seems only four projectors are required (and a spare is recommended)--at $4.5k each, this is the majority of the cost. (The sphere is $8,310; the computer is $2,500 and a spare is recommended [so $5k].)

Thanks for pointing that out; I was not aware of such being available.
Science on a Sphere has its own site (easily found by googling): http://sos.noaa.gov/What_is_SOS/index.html
The sphere is 68" (~173cm) in diameter and seems to be basically a screen for eight ("the projectors are at the corners of a virtual box with the sphere at the center") external projectors controlled by a computer.
(Using external projectors is probably more practical in set up and maintenance and more cost effective, but such would have disadvantages in terms of sensitivity to vibration of the screen or projector and blocking the path between screen and projector.)
The available datasets are biased toward weather/climate (as one would expect from being provided by NOAA), but there is an "Evolution of the Moon" dataset from NASA (in "Extras") and a collection of "Astronomy" datasets.

Unfortunately, the cost per unit--especially at low volume since even the manufacturing probably would have high NRE--of an electronic paper version would be extremely high. Support for color and fast refresh is also still somewhat new (so expensive). (And a high price would constrain sales volume, with the obvious effect on the price required to break even.)
I would guess that an active display would be more affordable, perhaps using something like Texas Instruments' DLP technology. (I am guessing that the micromirrors could be programmed to project onto a moderately diffusive curved surface. For lower volumes maximizing the use of commodity hardware--even at significant cost in software development--would seem to be important.)
Electronic paper would be so much nicer (visually and in terms of power consumption) than a projection-based globe, but I suspect the NRE would be far too great. (I doubt any makers of electronic paper would produce such a globe for the purpose of marketing.)
Perhaps I am excessively pessimistic--I admit I know almost nothing about the constraints of electronic paper--, but such a globe does not seem economically practical in the near future.

I think the true scale and proportion (i.e. lack of the distortion which any map has) is what makes a globe so appealing. Then there's just the simple good feeling of being able to directly hold it in your hand, like a cricket ball, and to be able to directly span off distances with finger and thumb. The "2D monitor universe" has taken away our sense of 3D touch when it comes to information processing.
The idea of a programmable globe surface is fantastic.

The globe has come off the shelf for the Olympics at my place, with the kids looking up countries during the opening ceremony and when a competitor's nation takes their fancy. A good way to learn.
Of course, memorising all of the states is easy if you live in Australia. ;-)

I am really REALLY enthused by this idea. There are so many things you could do with this -- starting with showing the continents as them moved over time -- then as you say human migrations -- and evolving political / country boundaries...